Advanced stacked cfchart over time

I have a stacked chart. It shows responses to a set of ten questions taken last month. Each question gets a stacked bar (showing the values for four possible answers). This works without a problem and the code is shown below. Responses for the same set of questions have been taken for this month. I would like to show the results for last month (stacked) next to this month (stacked), so the results for question last month are visible just behind the results for this month. Is this possible and what do I need to add, please?

      <cfchart
            xaxistitle="Question"
            yaxistitle="Answers"
            show3d="true"
            title="Answers"
            showlegend="true"      
            seriesplacement="stacked"
            > 
            <cfchartseries type="bar"
                  query="qCount"
                  itemcolumn="Question"
                  valuecolumn="disagree"
                  serieslabel="Disagree"      >
            <cfchartseries type="bar"
                  query="qCount"
                  itemcolumn="Question"
                  valuecolumn="Sdisagree"
                  serieslabel="Strongly Disagree"      >
            <cfchartseries type="bar"
                  query="qCount"
                  itemcolumn="Question"
                  valuecolumn="agree"
                  serieslabel="Agree">
            <cfchartseries type="bar"
                  query="qCount"
                  itemcolumn="Question"
                  valuecolumn="Sagree"
                  serieslabel="Strongly Agree" >
            </cfchartseries>
      </cfchart>